Various inventions and methods have been developed for gathering and analyzing operational data from a fleet of vehicles. Often these inventions depend on the use of data from a suite of highly-sophisticated sensors that is integrated into the vehicle. Other systems rely on the real-time wireless transmission of the captured data to a ground station or fleet terminal. These data acquisition systems depend on the analysis of the captured data, which must be done either on the vehicle, requiring a large amount of dedicated computing power to be integrated into the vehicle, or at a base station, requiring dedicated computing resources that must react to the data transmissions in real time.
U.S. Pat. Nos. 6,148,179, 6,160,998, 6,163,681, 6,167,239, 6,173,159, and 6,353,734 by Wright et al., and U.S. Pat. No. 6,167,238 by Wright, each describe a variation on a system that uses a wireless spread spectrum ground link-based system to communicate with aircraft. The common requirement for this group of patents is a system for sending data to or receiving data from an aircraft that depends on an on-board unit that obtains data from the aircraft and creates a communications link with a ground-based spread spectrum transceiver. The data collected from the aircraft can be transmitted to the ground-based transceiver whenever the aircraft is in communications range. This system works well for commercial aircraft such as passenger aircraft that routinely return to the location where the ground-based transceiver is set up, but is impractical and expensive for smaller flight operations or ground-based fleet operations.
US Patent Application Publications 2003/0041155, 2003/0055975, 2005/0220055, and U.S. Pat. No. 7,020,708 by Nelson et al. each describe data communication services that utilize public wireless systems to facilitate communication between a moving body and one or more ground terminals. The inventions described by Nelson et al. depend on the establishment of a radio communications path between the moving body and the ground terminals, and require the availability of public wireless systems. They will not work in areas where no wireless systems exist.
US Patent Application Publication 2004/0260777 and corresponding international publication WO 2004/045106 by Kolb et al. describe an aircraft flight data management system which collects aircraft data, formats it in the form of a binary or text file, and transmits the file via email to a ground station. This invention uses a rule-based software algorithm located in the aircraft as a means of determining when data should be sent via email to the ground station for analysis. This invention depends on a satellite or other wireless connection for the transmission of the email, as well as on the existence of a system with the email capability. These systems may be impractical and expensive for smaller flight operations or ground-based fleet operations.
U.S. Pat. No. 6,721,640 and corresponding international publication WO 01/60693 by Glenn et al. describe an event-based aircraft image and data recording system. Image data of various flight parameters is captured periodically during a flight and stored temporarily in a local memory buffer. When the system detects that certain pre-defined conditions exist based on an analysis of aircraft sensor data, a decision is made by the system to transfer the image data from the memory buffer to a separate storage device aboard the aircraft. This system depends on the presence of expensive imaging equipment on the aircraft. Image data, although potentially providing additional information for use in the investigation of an event such as the crash of an aircraft, is not a reliable means for capturing important flight data inasmuch as there are events such as wash-out caused by sunlight entering the camera wherein important flight data is lost. In addition, this is not a practical means for the storage and analysis of continuous data relating to the normal operation of an aircraft or other vehicle due to the excessive memory demands required by such a system, and the impracticability of reviewing this data for specific deviations from desired flight parameters.
US Patent Application Publication 2005/0197748 by Holst et al. describes a method and devices for wirelessly uploading and downloading data to and from a vehicle while it is in range of a coordinated network of vehicles. This invention, therefore, depends on the coordinated vehicle network, and will not reliably operate with a single vehicle or very small fleet of vehicles.
U.S. Pat. No. 6,397,128 by Todd describes a flight data recording system integrated with a flight data acquisition unit. This invention depends on the presence of an avionics standard communications bus to obtain data from external aircraft instrumentation subsystems. The flight data acquisition unit cannot itself sense or generate the flight data, but instead is dependent upon being tied into the avionics communications bus to obtain the data from other instruments that are tied into the bus. This invention cannot be used on aircraft or other vehicle types that lack a dedicated on-board communications bus.
U.S. Pat. No. 4,470,116 by Ratchford describes a digital flight data recording system that compares the actual recorded flight parameters to pre-defined optimum values based on an idealized model of an aircraft's flight schedule. The system creates a permanent record of the recorded data when the actual flight values differ significantly from the pre-defined optimum values. This system requires that each aircraft contain the computing platform necessary to store the pre-defined optimum values and to do the comparison. Requiring a computing platform on each aircraft in a fleet is often prohibitively expensive. The comparison to pre-defined values on the aircraft optimizes memory usage, however, there is no mechanism to store data pertaining to the entire flight.
US Patent Application Publication 2006/0057974 by Ziarno et al. describes a system and method of transmitting data from an aircraft. The system depends on the use of a PC card that includes a radio transceiver for transmitting aircraft data into the skin of the aircraft, with radiates the radio signal to a remote location. This system is designed for use on larger aircraft with a large metallic outer surface area, such that the skin of the aircraft acts as a passive antenna for the transmission of data. This system is not designed for use on smaller aircraft and vehicles, such as helicopters, trucks, or automobiles.
The inventions described above describe various ways of capturing and/or analyzing operational data from a fleet of vehicles. Most of these inventions depend on the real-time transmission of data over a wireless link to a ground-based station. Some depend on the presence of a complicated ground-based communications system, or depend on being tied into existing aircraft or vehicle subsystems to enable data collection. None of the inventions above describe a low-cost, self-contained system that does not depend on data from existing vehicle subsystems and which is ideally suited to gather operational data for a fleet of vehicles scattered over multiple locations, and provide an analysis of this operational data at a central location on a day to day operational basis.